Disk perforator for pipes in wells



A 1951 J. L. JOHNSTON 2,565,731

DISK PERFORATOR FOR PIPES IN WELLS Filed April 13, 1946 FigiS JAMEs L. JOHNS TON INVENTOR BY E) ATT N EYS Patented Aug. 28, 1951 DISK PnRron 'ronFoR'mrEsm WELLS James Luther-Johnston, Longviem Tex.,..assignor n rh wE sar a ohnsmn, ne w,

Appiication*April'1;3-,' 1946, Serial No. 661g939 The invention relates to. a closure perforaton for pipe. Under various sets of conditionsrit is: often necessary toprovide a frangibleon per-.- foratable-closure in apipeso as to prevent. the: how of fluid therethrough until a predetermined time. In order. to perforate: or. break: such' a010- sure; anassernblyis-provided which can bemoved: in the pipe so as-to strike the closure, causingrit. to be broken or perforated.

After the perforation or breaking of.:ther closure, itis desirable to then remove all of suchi perforator members from the pipe so as; to per.- initfull fiowcffiuid therethroug-h, andthe. present-invention contemplates the provisionof suchan arrangement.

It isone oftherobjects of the,;invention1to. pro

vide a perforator ofclosuresinxpipewhereby both.

the closure and perforator can .be removed, from; perforating. position by the-flow: of fluidafter; the; perforation.

Another. object of, theinvention is; to; provide aperiorator for closures in pipe which;substan e.

tially. fills-the pipe. so. that.the...flow. offluid along; the pipe afterthe perforation will remove. the; plunger so as to leavethe'pipe. openfor a.fu11 flow of fluid.

Another object of the invention, is; to: teme porarily look a pipe perforator in position in. the pipe so that it can be released by the-reactionof the perforating movement to thereafter flowwith,

the fluid in the pipe.

Another object of the invention is. toprqvidev a perforator for closures in pipe which has a 5831-, ing means there-around so as to be forced along with the flow of fluid released by the perfora tions.

Other and further objects of theinvention will be readily apparent when the following descrip: tion is considered in connection .witli.the.acconi panying drawings, wherein:

Fig. 1 is a vertical sectional view illustrating the assembly in a pipe in a well wherethe'plunger' is temporarily loclred in position;

Fig. 2'shows a modified arrangement-of, the plunger just about ready for movement to per-- forate'the closure.

Fig. 3 shows still another form of the invention with the plunger adjacent theclosure andiready to perform the perforating operation.

In Fig. l. a string ofpipez is shown. Pipe of this sort isusually located in a well-bore'andmay be in the form of easing, tubing; a formation testing stringof pipe, or any other pipe which-1t is desired to maintain closed until} a predeterminedtime. Thepipeis madeupof an upper section-3: and a lower section 4. The upperzsection is provided with: the. internal passage 5:: and;

the-lower section has a passage 6 which: ishere;

shown in Fig: l assornewhat reduced in diameter-1' as: compared-with the passage. 5.

The upper end of the pipe 4 has a threaded box member! so that a shoulder 8- supports a closure: 9 which rnay be a frangible or: perforat able disc or plate of any desired-.itype; Fig. I is a section to illustrate glass or sii nilar-materiaL however, it is intended that a thin metal* discor a disc-of frangible metal'or othersuitable corn position ina y be employedi This closure is-held' in position by the pinmember lfl-onthelower end of the upper pipe-section 3 ThiS-pin'- has the reduced passage II which in turn forms a shoulder 12; This shoulder is arranged to sup port the lower end of a coil spring [4 which in turn supports a plunger I5. This plunger has the pointed lower end; l6' which is adapted to engage-the closure 9 to perforate or break-the closure;- This plunger is made up of the body [1 ofwhichthe end It is a part. The plunger 'is-"enlarged at l9 so as to form a shoulder 20'which rests on the upper end-of thespring I4;

The upper end 23 of the plunger may be forined' in any desired manner so that it=may be gripped by a fishing tool if d esiredf'butparticularly soas' to present an upper surface 24 =which is arranged to be struck by an object dropped down through the pipe 2. Fig. 2 showssuch anobject 25 in the form of a weight having" the guide springs 27 on the sides thereof.-'. It is intended of course that any pipe nippleor object may be used. The function of thisobject is to strike the plunger I5 and to cause it to move down-sharply so as to perforate or break: the closure 9'. I v V 1 It is desirablethat the plunger be temporarily locked in the pipe so that it willnotb'e movedout of striking position and to accomplish this the interior of "the pipe is formed-with an annular recess which receives the balls 3| carriedin the openings 32 in a collar 33. The balls, the recess 39', and-the" plunger lfi are'of-such relative sizes-that the'plunger will fit: snuglythroughthe 3 a weight or other object can be dropped downwardly in the pipe 2 which may or may not be filled with liquid. The usual purpose of the closure 9 is to prevent the entrance of any fluid into the pipe 2 until such time as the pipe is properly located and the closure broken.

When the object falling through the pipe strikes the upper end 24 of the plunger, the plunger will move sharply downwardly so as to rupture the closure 9. This downward movement compresses the spring 14 so that as soon as the inertia of the parts is stopped, there will be a reaction of the spring, tending to throw the plunger upwardly. The collar 33, however, remains in locked position by the balls 3|. It is intended that the reaction of the spring M will throw the plunger upwardly sufficiently to remove the point from the punctured closure. When the lunger is to be removed, a suitable fishin tool can be low-- ered into the well bore to grip the tapered head 23 so as to exert a pull thereon and to raise the plunger to bring the reduced portion 31 up to the elevation of the balls 3|. This permits the balls to move inwardly out of the recess and release the assembly from the latched position. This upward movement in the plunger allows a full flow of fluid through the passage 6. The movement of the plunger assembly permits the fluid to move up in the well and of course if the fluid flow-is suflicient it may be elevated to thesurface.

In Fig. 2 a plunger is shown as having the pointed lower end 4| and having the closed internal cavity 42 to reduce the weight thereof. This plunger has the swab cups 455 thereon which are made up of the frusto-conical resilient cups 44 retained in position by the springs 45 Which are in turn confined at the lower end by a ring 66. 'Two of these swab cups are shown.

The closure is supported between the lower end of the upper pipe section 5| and the upper end of the lower pipe section 52 where the pipe sections are connected by a coupling or collar 53. This closure may be of any type as illustrated as being of material such as cast iron.

The upper end of the plunger has a head 55 thereon which is arranged to be struck by the weight or object 25.

This plunger 40 may be positioned as shown in Fig. 2 when the pipe is lowered into the well, then the weight 25 drops so as to break the closure 50 and the flow of fluid then movin upwardly in the pipe will exert a pressure under the swab cups so as to force the plunger out of the broken closure and upwardly in the pipe.

Fig. 3 shows a plunger body which is similar to that described in Fig. 2 except that a plunger rod BI is slidable therein and has the perforating head 62 on the lower end. A coil spring 63 is disposed between the body 60 and the retainer ring 64 is threaded on the upper end of the rod 61. The swab cups fit sufli'ciently tight inside of the pipe 66 to retain the parts in the position shown.

When the object 25 strikes the upper end B? of the rod 6|, it will be snapped downwardly to break the closure 50. The sprin 53, however, absorbs the impact of the weight so that the backing cups will not be sheared from the cylindrical body 60.

Broadly the invention contemplates a closure perforator for pipes wherein the fluid flow which is initiated by the breaking of the closure will remove the perforating assembly from within the closureand force it along the pipe.

4 What is claimed is: 1. A disc perforator assembly for well pipe com-' prising pipe connection, a frangible flat disc seal retained thereby, means movable in the pipe to engage and break said disc including a plunger, means to normally latch said plunger in the pipe above said disc, additional means movable in the pipe to strike and release said plunger to break said disc, and still additional means on said plunger to allow retraction to be effected from the broken disc.

2. A disc perforator for wells comprising a body, a lower end on said body to engage and break a frangible disc in the well pipe, and means also on said body to be engaged by fluid moving up in the well after the disc is broken so as to move said end out of the broken disc.

3. A perforator for pipe obstructions comprising a body, a member thereon to engage and break the obstruction, and means on the body to substantially fill the pipe around the said member so that the flow of fluid released by such break willthereafter remove said member from the break to be carried along the pipe with the flow of fluid.

4. A pipe in a well, a frangible closure for said pipe, a plunger to engage and perforate said closure, an enlargement about and above said plunger to substantially fill the pipe so that the flow of fluid upwardly in the pipe through the perforated closure after the perforation will move said plunger out of the perforated closure.

5. A pipe in a well, a frangible closure for said pipe, a plunger to engage and perforate said closure, an enlargement on said plunger to substantially fill the pipe this characteristic causing the flow of fluid in the pipe after the perforation to move said plunger out of the perforated closure, said enlargement comprising a collar about the plunger.

6. A pipe in a well, a frangible closure for said pipe, a plunger to engage and perforate said closure, an enlargement on said plunger to substantially fill the pipe, said enlargement comprising a collar about the plunger, and means in said collar and engaged by said plunger to lock the collar in the pipe.

7. A pipe in a well, a frangible closure for said pipe, a plunger to engage and perforate said closure, an enlargement on said plunger to substantially fill the pipe, said enlargement comprising a collar about the plunger, and means in said collar and engaged by said plunger to lock the collar in the pipe, said means being releasable by upward movement of the plunger after the perforation.

8.. A pipe in a well, a frangible closure for said pipe, a plulnger to engage and perforate said closure, an enlargement on said plunger to substantially fill the pipe so that the flow of fluid in the pipe after the perforation Will move said plunger out of the perforated closure, said means including a resilient sealing member carried by the plunger.

9. A pipe in a well, a frangible closure for said pipe, a plunger to engage and perforate said closure, an enlargement on said plunger to substantially fill the pipe this characteristic causing the flow of fluid in the pipe after the perforation to move said plunger out of the perforated closure in movable position thereon.

10. A pipe in a well, a frangible closure for said pipe, a plunger to engage and perforate said .closure, an enlargement on said plunger to substantially fill the pipe this characteristic causing the flow of fluid in the pipe after the perforation to move said plunger out of the perforated closure in movable position thereon, and a spring between said plunger and sealing means to absorb the shock of movement of the plunger.

11. A perforator for a closure in a pipe in a well comprising a collar in the pipe, a recess in the interior of the pipe, lock balls in the collar and fitting into said recess, a plunger in the collar and engaging said balls to hold them in looking position, a spring in the pipe supporting said plunger, a frangible closure adjacent said plunger, said plunger being movable downwardly when struck from above to perforate said closure, compress said spring and then be thrown upwardly by the spring to be released from the closure, and means on said plunger to be engaged so as to elevate said plunger to release said balls and collar to permit movement of the plunger and collar upwardly.

JANES- LUTHER JOHNSTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,884,165 Otis Oct. 25, 1932 2,232,688 Boynton Feb. 25, 1941 2,352,744 Stoddard July 4, 1944 

